Saturday, September 11, 2010

High Performance Annotations

The method I use to annotate with BIM is to add a material AND its Specification Section Number to the annotation for vendor neutral materials that are not specifically called out. (06 11 00_2x4 Dimensional Lumber – Species as Noted in the Contract Documents) or (07 54 00_TPO Membrane – Thickness as Noted in the Contract Documents). I use the term "Contract Documents" here as there are changes happening in the industry, and while the contract document now would be the Project Manual, in the future, it may not be. One may reference a tabular specification, or formatted data sheet of some kind. The descriptions are very fluid and allow for modification based on the amount of information known…

A knowledge manager may handle the annotations for the Roof Membrane Layer in a section view of a roof like this:

  • PP - (07 00 00_Roof as Noted in the Contract Documents)
  • SD - (07 50 00_Roof Membrane – As Noted in the Contract Documents)
  • DD - (07 54 00_Roof Membrane - Thermoplastic – As Noted in the Contract Documents)
  • CD - (07 54 23_Roof Membrane –.060 TPO – Tan)
  • Post Bid - (GAF EverGuard .060 TPO Membrane – Tan)

The idea is to give an appropriate description based on the amount of information known at a given time, and reference the Contract documents for the next pieces of information which may be necessary. This allows the annotation to always be correct, regardless of how much effort is put into the annotations, or if they never get updated past Schematic. I use phases as an example above, but I see phases as we know them disappearing to some degree with the growth of BIM. Because effort is recyclable in BIM, we can actually have detail views in Schematic Design that have merit. Standardized views can be moved from place to place within a template project, and only the annotations need be moved in order to create "Progress Drawings" at various phases of the project.

All in all, It's my belief that the concept of keynoting really only pertains to the drawings, which are ultimately viewed by the Contractor. With my background in General Contracting, I truly think that requiring them to reference information in a specification in order to get the BASIC information that they need to do their job to me is just plain LAZY! Drawings should follow the same CSI principles as Specifications (Clear, Concise, Complete, Correct) and the fifth C; Consistent. Keynoting makes incomplete drawings, as there is no single unified keynote structure, and there is no practical way to take into consideration EVERY possible component within a given specification section. It took over 1200 different BIM materials for a metal framing manufacturer to represent their Metal Stud offerings which consider dimension, yield strength, web depth and spacing.

Drawings are created before specifications, and BIM is the root of both. As information goes into the Model, it becomes a function of the drawing FIRST, and the attributed information becomes a tabular specification which can be used to develop a text based document. It is actually very simple (and very beneficial) to add the attributed information into the individual materials and components, as BIM provides not only the ability to TOGGLE between keynote, and annotation globally, but to actually concatenate attributes to create an accurate Callout.

The syntax for annotating a material goes something like this:

  • Keynote Only: [MF Number]
  • Keynote Only: [07 54 23]


  • PP: [MF Number]_[Component] [Type]
  • PP: [07 00 00]_[Roof] [as Noted in the Contract Documents]
  • PP: [07 00 00_Roof as Noted in the Contract Documents]


  • SD: [MF Number]_[Component] [Type] – [Material]
  • SD: [07 50 00]_[Roof] [Membrane] – [As Noted in the Contract Documents]
  • SD: [07 50 00_Roof Membrane – As Noted in the Contract Documents]

  • DD: [MF Number]_ [Component] [Type] – [Material]
  • DD: [07 54 00]_[Roof] [Membrane] – [Thermoplastic]
  • DD: [07 54 00_Roof Membrane - Thermoplastic – As Noted in the Contract Documents]

  • CD: [MF Number]_ [Component] [Type] – [Thickness] [Material] – [Color]
  • CD: [07 54 23]_[Roof] [Membrane] – [.060] [TPO] – [Tan]
  • CD: [07 54 23_Roof Membrane –.060 TPO – Tan]

  • Post Bid: [Manufacturer]_ [Trade Name] – [Thickness] [Material][Type] – [Color]
  • Post Bid: [GAF] [EverGuard] [.060] [TPO] [Membrane] – [Tan]
  • Post Bid: [GAF EverGuard .060 TPO Membrane – Tan]

Because of this structure, I use ONLY the 6 digits of MasterFormat, with no following enumeration that corresponds to a construction or specific material. A keynote is great if a machine needs to read it, but we are not machines. We are humans who want to see the information that we need, not have to follow a path in order to reference a different document. The BIM database already does this for us, and by mapping the information in such a way that it is no additional effort to create the more detailed information, there is no reason NOT to use full text callouts. We are all collaborating on a project, and should consider the needs of the individuals who are actually using our deliverables.

I do understand that you can only put so much information on an E sized plot, however, with the on screen digital world right in front of us, changing scale, and creating additional sheets which apply to specific trades at a more detailed scale is a simple Duplicate w/ Detailing Command.

All of this information is searchable within the model, and allows for analysis, so by adding a few attributes to each material, an annotation is automatically created, and can be globally updated based on the status of the project, or who needs the information. Whether or not keynoting is relevant and useful is no longer an issue in my estimation; That ship has sailed already. I think the idea is how detailed the annotations need to be in order to suit the needs of EVERY member of the project. If BIM can automate the annotation and keynoting process by leveraging attributes from within the material, assembly or component, the bigger issue is the accepted taxonomy and structure for the information which needs to be managed.

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